U.S. patent application number 13/891051 was filed with the patent office on 2013-11-14 for light emitting device, method of fabricating the same and lighting system.
The applicant listed for this patent is Gam Gon Kim, Kwang Hee LEE. Invention is credited to Gam Gon Kim, Kwang Hee LEE.
Application Number | 20130299854 13/891051 |
Document ID | / |
Family ID | 48325524 |
Filed Date | 2013-11-14 |
United States Patent
Application |
20130299854 |
Kind Code |
A1 |
LEE; Kwang Hee ; et
al. |
November 14, 2013 |
LIGHT EMITTING DEVICE, METHOD OF FABRICATING THE SAME AND LIGHTING
SYSTEM
Abstract
A light emitting device according to an embodiment includes a
body including first and second side walls which correspond to each
other, third and fourth side walls which have lengths longer than
lengths of the first and second side walls, and a concave portion;
a first lead frame under the concave portion and the third side
wall; a second lead frame under the concave portion and the fourth
side wall; a light emitting chip on at least one of the first and
second lead frames; a molding member on the concave portion; a
first recess portion recessed from the first side wall toward the
second side wall and connected to a bottom of the body; and a
second recess portion recessed from the second side wall toward the
first side wall and connected to the bottom of the body.
Inventors: |
LEE; Kwang Hee; (Seoul,
KR) ; Kim; Gam Gon; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LEE; Kwang Hee
Kim; Gam Gon |
Seoul
Seoul |
|
KR
KR |
|
|
Family ID: |
48325524 |
Appl. No.: |
13/891051 |
Filed: |
May 9, 2013 |
Current U.S.
Class: |
257/88 |
Current CPC
Class: |
H01L 2224/92247
20130101; H01L 2224/73265 20130101; H01L 2924/1301 20130101; H01L
2224/32245 20130101; H01L 2224/73265 20130101; H01L 2224/48091
20130101; H01L 2224/48247 20130101; H01L 2224/92247 20130101; H01L
2224/49113 20130101; H01L 2224/73265 20130101; H01L 2224/73265
20130101; H01L 2924/00 20130101; H01L 2924/00014 20130101; H01L
2924/00 20130101; H01L 2224/32245 20130101; H01L 2924/00 20130101;
H01L 2224/48247 20130101; H01L 2224/48247 20130101; H01L 2224/32245
20130101; H01L 2924/00012 20130101; H01L 2224/48247 20130101; H01L
2224/32245 20130101; H01L 2224/48091 20130101; H01L 2924/1301
20130101; H01L 25/0753 20130101; H01L 33/486 20130101; H01L 33/62
20130101 |
Class at
Publication: |
257/88 |
International
Class: |
H01L 33/62 20060101
H01L033/62 |
Foreign Application Data
Date |
Code |
Application Number |
May 14, 2012 |
KR |
10-2012-0050963 |
Claims
1. A light emitting device comprising: a body including first and
second side walls which correspond to each other, third and fourth
side walls which have lengths longer than lengths of the first and
second side walls, and a concave portion therein; a first lead
frame under the concave portion and the third side wall; a second
lead frame under the concave portion and the fourth side wall; a
light emitting chip on at least one of the first and second lead
frames; a molding member on the concave portion; a first recess
portion recessed from the first side wall toward the second side
wall and connected to a bottom of the body; and a second recess
portion recessed from the second side wall toward the first side
wall and connected to the bottom of the body.
2. The light emitting device of claim 1, wherein the first lead
frame includes a first cavity lower than a bottom of the concave
portion and a first lead part protruding more than the third side
wall, the second lead frame includes a second cavity lower than the
bottom of the concave portion and a second lead part protruding
more than the fourth side wall, and the light emitting chip
includes a first light emitting chip disposed in the first cavity
and a second light emitting chip disposed in the second cavity.
3. The light emitting device of claim 2, wherein the first and
second recess portions are opposite to each other with respect to
at least one of the first and second cavities.
4. The light emitting device of claim 2, further comprising: a
third recess portion spaced apart from the first recess portion
under the first side wall of the body; and a fourth recess portion
spaced apart from the second recess portion under the second side
wall of the body, wherein the first and second recess portions are
opposite to each other with respect to the first cavity, and the
third and fourth recess portions are opposite to each other with
respect to the second cavity.
5. The light emitting device of claim 4, further comprising: a
fifth recess portion connecting the first recess portion to the
third recess portion under the first side wall and having a width
larger than a width of the first or third recess.
6. The light emitting device of claim 4, wherein a distance between
the first and third recess portions is larger than a distance
between bottoms of the first and second cavities.
7. The light emitting device of claim 2, wherein a width of at
least one of the first and second recess portions is less than an
interval between bottoms of the first and second cavities, and a
depth of at least one of the first and second recess portions is
less than a distance between a bottom of the first cavity and the
first side wall.
8. The light emitting device of claim 7, wherein at least one of
the first and second recess portions has a width larger than an
interval between bottoms of the first and second cavities.
9. The light emitting device of claim 1, wherein the first and
second side walls are inclined with respect to a bottom of the
body, and the first and second recess portions have height less
than a thickness of the first and second lead frames when measured
from the bottom of the body.
10. The light emitting device of claim 1, wherein each of the first
and second side walls has an upper region inclined with respect to
the bottom of the body and a lower region perpendicular to the
bottom of the body, and the first and second recess portions are
recessed from the lower regions of the first and second side walls
of the body.
11. The light emitting device of claim 2, wherein the first and
second side walls have a length at least two times longer than a
length of the third and fourth side walls.
12. The light emitting device of claim 1, wherein at least one of
the first and second recess portions includes a concave portion or
a convex portion.
13. The light emitting device of claim 2, wherein the first recess
portion is disposed corresponding to a side surface of the first
cavity, the second recess portion is disposed corresponding to a
side surface of the second cavity, and the first and second recess
portions are offset from each other based a gap part between the
first and second lead frames.
14. The light emitting device of claim 1, the first and second
recess portions are disposed corresponding to a gap part between
the first and second lead frames.
15. The light emitting device of claim 1, wherein at least one of
the first and second recess portions has a depth in a range of 30
.mu.m to 100 .mu.m and a width in a range of 50 .mu.m to 500
.mu.m.
16. A light emitting device comprising: a body including first and
second side walls which correspond to each other, third and fourth
side walls which have lengths longer than lengths of the first and
second side walls, and a concave portion therein; a first lead
frame under the concave portion; a second lead frame under the
concave portion; a first light emitting chip on the first lead
frame; a second light emitting chip on the second lead frame; a
molding member on the concave portion; a plurality of first recess
portions recessed from the first side wall toward the second side
wall; and a plurality of second recess portions recessed from the
second side wall toward the first side wall, wherein the plurality
of first recess portions are spaced apart from each other by an
interval larger than an interval between the first and second light
emitting chips.
17. The light emitting device of claim 16, wherein a length of the
first and second side walls is at least three times longer than a
length of the third and fourth side walls.
18. The light emitting device of claim 17, wherein the first recess
portions and the second recess portions are open from a bottom of
the body.
19. The light emitting device of claim 17, further comprising: a
third recess portion connected to the first recess portions.
20. The light emitting device of claim 16, further comprising: a
connecting frame disposed on a bottom of the concave portion and
electrically connected to the first and second light emitting
chips.
Description
[0001] The present application claims priority under 35 U.S.C.
.sctn.119(a) of Korean Patent Application No. 10-2012-0050963 filed
on May 14, 2012, which is hereby incorporated by reference in its
entirety.
BACKGROUND
[0002] The embodiment relates to a light emitting device, a method
of fabricating the same and a lighting system.
[0003] Light emitting devices, for example, light emitting diodes
(LEDs) are semiconductor devices that convert electric energy into
light and extensively used as next-generation light sources in
place of conventional fluorescent lamps and glow lamps.
[0004] Since the LED generates the light by using the semiconductor
device, the LED may represent low power consumption as compared
with the glow lamp that generates the light by heating tungsten or
the fluorescent lamp that generates the light by urging ultraviolet
ray, which is generated through the high-voltage discharge, to
collide with a fluorescent substance.
[0005] In addition, the LED generates the light by using the
potential gap of the semiconductor device, so the LED is
advantageous as compared with conventional light sources in terms
of life span, response characteristics, and environmental-friendly
requirement.
[0006] In this regard, various studies have been performed to
replace the conventional light sources with the LEDs. The LEDs are
increasingly used as light sources for lighting devices, such as
various lamps used indoors and outdoors, liquid crystal displays,
electric signboards, and street lamps.
SUMMARY
[0007] An embodiment provides a light emitting device including a
body having a side wall of a novel structure.
[0008] The embodiment provides a light emitting device including a
recess portion in at least one of side walls of a body.
[0009] The embodiment provides a light emitting device including a
plurality of recess portions in a bottom of a body.
[0010] The embodiment provides a light emitting device including a
plurality of recess portions in the first and second side walls of
side walls which correspond to each other.
[0011] The embodiment provides a light emitting device including
recess portions in the first and second side walls corresponding to
a side surface of a cavity in which a light emitting chip is
disposed.
[0012] The embodiment provides a method of fabricating a light
emitting device which can support a body by using a hanger inserted
into a recess portion when the body is injection-molded.
[0013] According to the embodiment, there is provided a light
emitting device including a body including first and second side
walls which correspond to each other, third and fourth side walls
which have lengths longer than lengths of the first and second side
walls, and a concave portion therein; a first lead frame under the
concave portion and the third side wall; a second lead frame under
the concave portion and the fourth side wall; a light emitting chip
on at least one of the first and second lead frames; a molding
member on the concave portion; a first recess portion recessed from
the first side wall toward the second side wall and connected to a
bottom of the body; and a second recess portion recessed from the
second side wall toward the first side wall and connected to the
bottom of the body.
[0014] According to the embodiment, there is provided a light
emitting device including a body including first and second side
walls which correspond to each other, third and fourth side walls
which have lengths longer than lengths of the first and second side
walls, and a concave portion therein; a first lead frame under the
concave portion; a second lead frame under the concave portion; a
first light emitting chip on the first lead frame; a second light
emitting chip on the second lead frame; a molding member on the
concave portion; a plurality of first recess portions recessed from
the first side wall toward the second side wall; and a plurality of
second recess portions recessed from the second side wall toward
the first side wall, wherein the first recess portions are spaced
apart from each by a gap larger than a gap between the first and
second light emitting chips.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view showing a light emitting device
according to a first embodiment;
[0016] FIG. 2 is a sectional view taken along line A-A of the light
emitting device in FIG. 1;
[0017] FIG. 3 is a view of the light emitting device in FIG. 1 when
viewed from a first side;
[0018] FIG. 4 is a view of the light emitting device in FIG. 1 when
viewed from a second side;
[0019] FIG. 5 is a partially enlarged view of FIG. 3;
[0020] FIG. 6 is a rear view of the light emitting device of FIG.
1;
[0021] FIG. 7 is a partially enlarged view of FIG. 6;
[0022] FIG. 8 is a sectional view taken along line B-B of the light
emitting device in FIG. 6;
[0023] FIG. 9 is a sectional view at a central side of the light
emitting device in FIG. 6;
[0024] FIGS. 10 to 14 are views illustrating a process of
fabricating a light emitting device;
[0025] FIGS. 15 and 16 are views showing another arrangement of the
recess portions in the light emitting device of FIG. 6;
[0026] FIG. 17 is a view showing a hanger position when fabricating
the light emitting device of FIGS. 15 and 16;
[0027] FIGS. 18 and 19 are side sectional views of a light emitting
device according to the second embodiment and show a hanger and a
shape of a recess;
[0028] FIGS. 20 and 21 are side sectional views of a light emitting
device according to the third embodiment and show another shape of
a recess portion and a hanger;
[0029] FIGS. 22 and 23 are side sectional views of a light emitting
device according to an embodiment, and show an example of a
modified shape of a recess;
[0030] FIGS. 24 to 27 are rear views of a light emitting device
according to the fifth embodiment and show an example of a recess
portion having modified position and shape;
[0031] FIGS. 28 and 29 are rear views of a light emitting device
according to the sixth embodiment, and show a length of a recess
portion and a hanger;
[0032] FIGS. 30 to 32 are rear views of a light emitting device
according to the seventh embodiment, and show examples of a
modified recess;
[0033] FIG. 33 is a plan view of a light emitting device according
to the eighth embodiment;
[0034] FIGS. 34 to 37 are rear views of the light emitting device
of FIG. 33;
[0035] FIG. 38 is a plan view showing a light emitting device
according to the ninth embodiment;
[0036] FIG. 39 is a plan view showing a light emitting device
according to the tenth embodiment;
[0037] FIG. 40 is a rear view of the light emitting device of FIG.
39;
[0038] FIG. 41 is a side sectional view of the light emitting
device of FIG. 39;
[0039] FIG. 42 is a sectional view showing one example of a light
emitting chip in a light emitting device according to the
embodiment;
[0040] FIG. 43 is a sectional view showing another example of a
light emitting chip in a light emitting device according to the
embodiment;
[0041] FIG. 44 is a perspective view showing a display apparatus
having the light emitting device according to the embodiment.
[0042] FIG. 45 is a sectional view showing a display apparatus
according to the embodiment;
[0043] FIGS. 46 to 48 are views showing a lighting apparatus
according to the embodiment; and
[0044] FIGS. 49 and 50 are views showing other examples of a
lighting apparatus according to the embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0045] In the description of the embodiments, it will be understood
that when a substrate, a frame, a sheet, a layer, or a pattern is
referred to as being "on" another substrate, another frame, another
sheet, another layer, or another pattern, it can be "directly" or
"indirectly" on the other substrate, the other frame, the other
sheet, the other layer, or the other pattern may also be present.
In contrast, when a part is referred to as being "directly on"
another part, the intervening layer is not present.
[0046] Hereinafter, embodiments will be clearly comprehended by
those skilled in the art with reference to accompanying drawings
and the description of the embodiments. The thickness and size of
each layer shown in the drawings may be exaggerated, omitted or
schematically drawn for the purpose of convenience or clarity. In
addition, the size of elements does not utterly reflect an actual
size. The same reference numbers will be assigned the same elements
throughout the drawings.
[0047] Hereinafter, a light emitting device according to the
embodiment will be described with reference to the accompanying
drawings.
[0048] FIG. 1 is a perspective view illustrating a light emitting
device according to a first embodiment, FIG. 2 is a sectional view
taken along line A-A of the light emitting device in shown FIG. 1,
FIG. 3 is a view showing the light emitting device of FIG. 1 when
seen from a first side, FIG. 4 is a view showing the light emitting
device of FIG. 1 when seen from a second side, FIG. 5 is a
partially enlarged view of the light emitting device shown in FIG.
3, FIG. 6 is a rear view showing the light emitting device of FIG.
1, FIG. 7 is a partially enlarged view of the light emitting device
of FIG. 2, FIG. 8 is a sectional view taken along line B-B of the
light emitting device in shown FIG. 6, and FIG. 9 is a sectional
view of a central portion of the of the light emitting device shown
in FIG. 6.
[0049] Referring to FIGS. 1 to 9, the light emitting device 100
includes a body 10 having a concave portion 16, a first lead frame
21 having a first cavity 25 under the concave portion 16, a second
lead frame 31 having a second a cavity 35 under the concave portion
16, a molding member 40, a connecting frame 46, and light emitting
chips 71 and 72. The connecting frame 46 may be omitted from the
light emitting device 100.
[0050] The body 10 may include an insulating material, a nonmetal
material or a conductive material. The body 10 may include at least
one of a resin material, such as Polyphthalamide (PPA), silicon or
epoxy, a metallic material, photo sensitive glass (PSG), a ceramic
material, sapphire (Al.sub.2O.sub.3), and a printed circuit board
(PCB) having a circuit pattern. For example, the body 10 may
include a resin material such as Polyphthalamide (PPA), silicon or
epoxy. The body 110 may be formed of epoxy or silicon. A filler
including metal oxide such as TiO.sub.2 or SiO.sub.2 may be added
to the body 10 to increase reflecting efficiency.
[0051] The body 10 may have a polygonal outer appearance, such as a
triangle shape, a rectangular shape or a square shape, a circular
shape, or a shape having a curved surface, when viewed from the
top.
[0052] The body 10 includes the concave portion 16 having a
predetermined depth from the top surface of the body 10 and an
opened upper portion, a side surface 16-1 of the concave portion 16
and a bottom. The concave portion 16 may be formed in various
structures such as a cup structure, a cavity structure or a recess
structure, but the embodiment is not limited thereto. The side
surface 16-1 of the concave portion 16 may be perpendicular or
inclined to the bottom of the body 10. The body 10 may have a
polygonal outer appearance, such as a rectangular shape or a square
shape, a circular shape, or a shape having a curved surface, when
viewed from the top The concave portion 16 may have a circle shape,
an ellipse shape, a polygon (for example, a square) shape, and a
polygon shape having curved corners when viewed from the top.
[0053] The body 10 may include a plurality of side walls, for
example, at least four side walls 11, 12, 13 and 14. The first to
fourth side walls 11 to 14 will be described as one example. The
first side wall 11 faces the second side wall 12, and the third
side wall 14 faces the fourth side wall 14.
[0054] At least one of the side walls 11 to 14 may be disposed to
be perpendicular to or inclined to the bottom of the body 10. For
example, as shown in FIG. 5, the side walls 11 to 114 of the body
10 may be inclined at a first angle .theta.1 with respect to a
segment perpendicular to the bottom 17 of the body 10, and the
first angle .theta.1 may be in the range as shown in FIGS. 1 to 10.
Since the side walls 11 to 14 of the body 10 are inclined, when
molding the body 10, a mold for molding the body 10 is easily
separated from the body 10.
[0055] A length X1 of the first and second side walls 11 and 12 may
be different from a length Y1 of the third and fourth side walls 13
and 14. For example, the length X1 of the first and second side
walls 11 and 12 may be longer than the length Y1 of the third and
fourth side walls 13 and 14. The length X1 of the first or second
side wall 11 or 12 may be the gap between the third and fourth side
walls 13 and 14. A direction of a first axis X which is a
longitudinal direction of the body 10 passes through the centers of
the second and third cavities 25 and 35 and the length X1 of the
first or second side wall 11 or 12 may be the gap between the third
and fourth side walls 13 and 14. A direction of a second axis Y
which is the width direction of the body 10 may be a direction
perpendicular to the first axis X, and may be the gap between the
first and second side walls 11 and 12.
[0056] The length X1 of the first and second side walls 11 and 12
may be the length of the body 10 and the length Y1 of the third and
fourth side walls 13 and 14 may be the width of the body 10.
[0057] The length X1 of the first and second side walls 11 and 12,
which is the length of the body 10, is for example, two or three
times longer than that Y1 of the third and fourth side walls 13 and
14 which is the width of the body 10. Since the length X1 of the
body 10 is longer than the width Y1 of the body 10, a middle
portion of the body 10 may be bent or damaged when performing an
injection molding process. The embodiment is provided for
preventing the body 10 from being damaged due to the length X1 of
the body 10, thereby preventing the yield from being decreased. The
first lead frame 21 is disposed in a first region of the concave
portion 16, and a portion of the first lead frame 21 is disposed on
a bottom of the concave portion 16. A first cavity 25, which has a
depth lower than the bottom of the concave portion 16, is provided
in an inner side region of the first lead frame 21. The first
cavity 25 includes a concave shape, such as a cup or a recess,
which is concaved from the concave portion 16 toward the bottom of
the body 10.
[0058] A side surface and a bottom of the first cavity 25 may be
formed by the first lead frame 21 and an outer side surface of the
first cavity 25 may be bent to be inclined or perpendicular to the
bottom of the first cavity 25. Corresponding two side surfaces of
the side surfaces of the first cavity 25 may be inclined at the
same angle or the mutually different angles. The bottom of the
first cavity 25 may be made flat and the first region may
correspond to a region in which the first light emitting chip 71 is
disposed.
[0059] The second lead frame 31 is disposed in a second region
spaced apart from the first region of the concave portion 16, and a
portion of the second lead frame 31 is disposed on the bottom of
the concave portion 16. A second cavity 35, which has a depth lower
than the bottom of the concave portion 16, is provided in an inner
side region of the second lead frame 31. The second cavity 35
includes a concave shape, such as a cup or a recess, which is
concaved from the top surface of the second lead frame 31 toward
the bottom of the body 10. The bottom and side surfaces of the
second cavity 35 may be formed by the second lead frame 31, and the
side surfaces of the second cavity 35 may be bent to be may be
inclined or perpendicular to the bottom of the second cavity 35.
Corresponding two side surfaces of the side surfaces of the second
cavity 35 may be inclined at the same angle or the mutually
different angles. The bottom of the second cavity 35 may be made
flat and the second region may correspond to a region in which the
second light emitting chip 72 is disposed.
[0060] The first cavity 25 and the second cavity 35 may be formed
in the same shape and in a polygon or ellipse shape when viewed
from the top. Further, the first and second cavities 25 and 35 may
be disposed in a point symmetry or line symmetry structure when
viewed from the top. Each of the first and second cavities 25 and
35 may include a base part which corresponds to a bottom region, a
side part bent from the base part, and an outer part bent from the
side part.
[0061] As show in FIG. 6, the bottoms of the first and second
cavities 25 and 35 may have a rectangular shape, a square shape, a
partially curved shape, a circle shape or an ellipse shape, but the
embodiment is not limited thereto. The bottoms 22 and 32 of the
first and second cavities 25 and 35 may be exposed from a lower
portion of the body 10 and may be disposed on the same plane as the
bottom of the body 10. When the bottoms 22 and 32 of the first and
second cavities 25 and 35 may be disposed the same plane as the
bottom of the body 10, an adhesive strength of a bonding member
such as solder may be improved. Further, the first and second
cavities 25 and 35 conduct the heat generated from the first and
second light emitting chips 71 and 72.
[0062] As shown in FIGS. 2 to 6, the first lead frame 21 may
include a first lead part 23. The first lead part 23 may be
disposed at the bottom 17 of the body 10 and may be protruded to
the third side wall 13 of the body 10. The second lead frame 31 may
include a second lead part 33. The second lead part 33 may be
disposed at the bottom 17 of the body 10 and may be protruded to
the fourth side wall 14 of the body 10. The first and second lead
parts 23 and 33 may be disposed the same plane as the bottom 17 of
the body 10, an adhesive strength of a bonding member such as
solder may be improved.
[0063] The first lead frame and part 21 and 23 and the second lead
frame and part 31 and 33 may be mounted on a circuit substrate. The
first and second lead frames 21 and 31 may have a thickness of 0.15
mm or 0.18 mm more, or for example, in the range of 0.20
mm.about.0.25 mm. The first and second lead frames 21 and 31
perform a function of a lead frame for supplying power.
[0064] The connecting frame 46, which is spaced apart from the
first and second lead frames 21 and 31 in the bottom region of the
concave portion 16, serves as a middle connecting terminal. As
shown in FIG. 3, a portion 46-1 of the connecting frame 46 may be
exposed on the first side wall 11 of the body 10. If the first and
second lead frames 21 and 31 are connected to the first and second
light emitting chips 71 and 72, the connecting frame 46 may be
removed.
[0065] The first and second lead frame 21 and 31 and the connecting
frame 46 may include a metallic material, for example, at least one
of titanium (Ti), copper (Cu), nickel(Ni), gold (Au), chrome (Cr),
tantalum (Ta), platinum (Pt), tin (Sn), silver (Ag), and phosphor
(P), and may be configured as a single metal layer or multi-metal
layers. The first and second lead frame 21 and 31 and the
connecting frame 46 may have the same thickness, but the embodiment
is not limited thereto.
[0066] The first light emitting chip 71 is disposed in the first
cavity 25 of the first lead frame 21 and is adhesive onto the first
cavity 25 with a first adhesive member 81. The second light
emitting chip 72 is disposed in the second cavity 35 of the second
lead frame 31 and is adhesive onto the second cavity 35 with a
second adhesive member 82. The first and second adhesive members 81
and 82 may be an insulation adhesive or a conductive adhesive. The
insulation adhesive may include a material such as epoxy or
silicon, and the conductive adhesive may include a bonding material
such as a solder. The first and second adhesive members 81 and 82
may further include metallic oxide in order to improve thermal
conductivity, but the embodiment is not limited thereto.
[0067] The first and second light emitting chips 71 and 72 may
selectively emit light in the range between a visible ray band and
an ultraviolet (UV) band. For example, one of a red LED chip, a
blue LED chip, a green LED chip, a yellow green LED chip, and a
white LED chip may be selected as the first and second light
emitting chips 71 and 72. Each of the first and second light
emitting chips 71 and 72 includes an LED chip having at least one
of a compound semiconductor of group III-V elements and a compound
semiconductor of group II-VI elements.
[0068] The first light emitting chip 71 is connected to the first
lead frame 21 disposed on the bottom of the concave portion 16
through a first wire 73 and is connected to the connecting frame 46
through a second wire 74. The second light emitting chip 72 is
connected to the connecting frame 46 through a third wire 75 and is
connected to the second lead frame 31 disposed on the bottom of the
concave portion 16 through a fourth wire 76. The connecting frame
46 electrically connects the first light emitting chip 71 to the
second light emitting chip 72.
[0069] A protective device (not shown) may be disposed on a portion
of the first or second lead frame 21 or 31. The protective device
may be implemented by using a thyristor, a zener diode, or
transient voltage suppression (TVS). The zener diode may be used to
protect a light emitting chip from an electro static discharge
(ESD). The protective device may be connected in parallel to the
first and second light emitting chips 71 and 72 to protect the
first and second light emitting chips 71 and 72.
[0070] The molding member 40 may be formed in at least one of the
concave portion 16, and the first and second cavities 25 and 26.
For example, the molding member 40 may be formed in the concave
portion 16, and the first and second cavities 25 and 26. The
molding member 40 may be formed of a transparent resin material
such as silicon or epoxy, and may be formed in a single layer or a
multilayer.
[0071] Further, the molding member 40 may include phosphor. The
phosphor may be added to the molding member 40 formed in at least
one region of the first and second cavities 25 and 35, but the
embodiment is not limited thereto. The phosphor may include one
selected from YAG, TAG, Silicate, Nitride, and oxy-nitride
materials. The phosphor may include at least one of a red phosphor,
a yellow phosphor, and a green phosphor, but the embodiment is not
limited thereto. A top surface of the molding member 40 may have at
least one of a flat shape, a concave shape, a convex shape, and a
light exit surface, but the embodiment is not limited thereto.
[0072] The top surface of the molding member 40 may be a light exit
surface. An optical lens may be provided in an upper portion of the
molding member 40, and may include a convex lens, a concave lens or
a convex lens having a total reflection surface at a central
portion thereof, but the embodiment is not limited thereto.
[0073] Referring to FIGS. 1, 3, 4 and 6, at least one of the first
and second side walls 11 and 12 of the body 10 may include at least
one recess structure which is recessed at a predetermined depth
from the first and second side walls 11 and 12 in an inner
direction of the body 10. The recess structure of the body 10 is
concaved from the first and second side walls 11 and 12 toward the
inner direction of the body 10. A hanger, which supports the body
10 when injection-molding the body 10, may be inserted into the
recess structure, so that the damage of the body 10 may be
prevented. Hereinafter, the recess structure will be described as a
recess portion for the purpose of explanation and one or a
plurality of recess portions may be disposed.
[0074] As shown in FIGS. 3, 4 and 6, for example, first and second
recess portions 51 and 52 are disposed in the first side wall 11
and third and fourth recess portions 53 and 54 are disposed in the
second side wall 12 of the body 10. An interval D1 between the
first and second recess portions 51 and 52 is equal to an interval
between the third and fourth recess portions 53 and 54. An interval
D1 between the first and second recess portions 51 and 52 is equal
to or larger than a distance G1 between the bottoms 22 and 32 of
the first and second cavities 25 and 35. The first and third recess
portions 51 and 53 face each other and the second and fourth recess
portions 52 and 54 face each other. As shown in FIG. 7, a virtual
segment of connecting the first recess portion 51 to the third
recess portion 53 may be disposed in a direction which is
perpendicular to the line X2 parallel to the first or second side
wall 11 or 12. The virtual segment of connecting the first recess
portion 51 to the third recess portion 53 may be disposed in
parallel to a virtual segment of connecting the second recess
portion 52 to the fourth recess portion 54.
[0075] The first to fourth recess portions 51 to 54 are opened from
the bottom 17 of the body 10 and are connected to the bottom 17 of
the body 10.
[0076] As shown FIG. 5, the distance D2 from the first recess
portion 51 to the third side wall 13 may be equal to the distance
from the third recess portion 53 to the third side wall 13 and the
distance from the second recess portion 52 to the fourth side wall
14 may be equal to the distance from the fourth recess portion 54
to the fourth side wall 14. The first and third recess portions 51
and 53 may be placed to face each other. The second and fourth
recess portions 52 and 54 may be formed at the positions at which
the second and fourth recess portions 52 and 54 correspond to each
other or are overlapped in a horizontal direction. The bottom of
the first cavity 25 is disposed between the first and third recess
portions 51 and 53 and the bottom of the second cavity 35 is
disposed between the second and fourth recess portions 52 and
54.
[0077] The distance D2 between the first recess portion 51 and the
third side wall 13 of the body 10 may be 130 .mu.m or more for
example, in the range of 130 .mu.m.about.500 .mu.m. Since the
distance D2 is longer than the width (T3 in FIG. 2) of the top
surface of the body 10, an impact transferred to the body 10
through the first recess portion 51 may be minimized. The width T3
of the top surface 15 of the body 10 may be 130 .mu.m or more and
may be narrower than the distance D2. That is, the recess portions
51 to 54 of the body 10 may be formed to be deeper than the width,
that is, the rim region of the top surface of the body 10. The
width T3 may be the gap between the third or fourth side wall 13 or
14 and the concave portion 16, that is, the minimum gap.
[0078] As shown in FIG. 8, the width T4 of the top surface of the
body 10 is the gap between the first or second side wall 11 or 12
and the concave portion 16. The width T4 may be equal to or
narrower than the width T3, but the embodiment is not limited
thereto.
[0079] As shown in FIGS. 5 and 8, since the heights of the first to
fourth recessed 51 to 54 may be the distances from the bottom of
the body 10 and may be the same, only the height T2 of the first
recess portion 51 will be described below. The height T2 of the
first recess portion 51 may be formed from the bottom 17 of the
body 10 at 15 .mu.m to more. For example, the height T2 of the
first recess portion 51 may be formed in the range of 15
.mu.m.about.250 .mu.m. The height T2 of the first recess portion 51
may be equal to the thickness T1 of the lead frames 21 and 31 or
may be thinner than the thickness T1. When the height T2 of the
first recess portion 51 is greater than that in the range, the
solidity of the body 10 may be weakened.
[0080] Refer to the width W1 of the first recess portion 51 for the
width of the first to fourth recess portions 51, 52, 53 and 54. The
width W1 of the first recess portion 51 may be 50 .mu.m or more,
and for example, in the range of 50 .mu.m-500 .mu.m. Since the
width, which the inserting protrusion of the hanger can support, is
50 .mu.m or more, the width W1 of the first recess portion 51 may
be formed to be 50 .mu.m or more or to be larger than the
thicknesses of the first and second lead frames 21 and 31. Further,
the width W1 may be 1/10 or less based on the length X1 of the body
10, but the embodiment is not limited thereto. When the widths W1
of the first to fourth recess portions 51 to 54 are narrower than
that in the range, the body 10 may not be supported. And, when the
width W1 is out of the range, the strength of the body 10 may be
weakened. The width W1 of the first recess portion 51 may be
narrower than that of one of the side walls of the first and second
light emitting chips 71 and 72. Further, the width W1 of the first
recess portion 51 may be formed to be narrower than the distance G1
between the first and second cavities 25 and 35 shown in FIG. 6. In
addition, the width W1 of the first recess portion 51 may be formed
to be narrower than the widths (in X axis direction) of the bottoms
of the first and second cavities 25 and 35.
[0081] Referring to FIGS. 7 and 8, the depths D4 of the first to
fourth recess portions 51 to 54 may be equal to or different from
the width W1, and for example, may formed to be in the range of 30
.mu.m-130 .mu.m. When the width W1 is 100 .mu.m or less, the depths
D4 of the first to fourth recess portions 51 to 54 may be formed to
be in the range of 50 .mu.m.about.100 .mu.m. The depth D4 of the
first recess portion 51 may be narrower than the width of one of
the side surfaces of the first and second light emitting chips 71
and 72. The depth D4 may be shorter than the distances between the
first and second side walls 11 and 12 and the bottoms of the first
and second cavities 25 and 35.
[0082] The depths D4 of the recess portions 51 to 54 may be deeper
than the width T3 of the top surface 15 of the body 10. For
example, the depths D4 of the recess portions 51 to 54 may be
formed to be deeper than the minimum gap of the gaps between the
first to fourth side walls 11 to 14 and the concave portion 16. For
example, the depths D4 of the recess portions 51 to 54 may be
formed to be deeper than the width T3 or T4 of the top surface of
the body 10. For example, the depth D4 may be deeper than the width
T4 of the top surface and may be narrower than the distance B4
between the bottom of the concave portion 16 and the first side
wall 11. When the depth D4 is deeper than the distance B4, the
first and second side walls 11 and 12 are weakened, and when the
depth D4 is narrower than the width T4 of the top surface, the
performance of the hanger is deteriorated.
[0083] As shown in FIG. 6, at least two recess portions 51 to 54
may exist in the first or second side wall 11 or 12 of the body 10.
At least four recess portions, for example, six to eight recess
portions may exist in the first or second side wall 11 or 12. As
the length X1 of the body 10 is lengthened in the long-axis
direction, the number of recess portions may be increased, but the
embodiment is not limited thereto. The recess portions 51 to 54 may
be formed symmetrically to the segment extending in the
longitudinal direction X1 by passing through the centers of the
cavities 25 and 35 of the body 10, but the embodiment is not
limited thereto.
[0084] Referring to FIGS. 1 and 6, the first and third recess
portions 51 and 53, which are disposed in an edge region in the
bottom 17 of the body 10, are disposed near a segment Y2 which
extends through the center of the bottom surface 22 of the first
cavity 25 in perpendicular to the bottom surface 22 of the first
cavity 25. The second and fourth recess portions 52 and 54 are
disposed near a segment Y3 which extends through the center of the
bottom surface 32 of the second cavity 35 in perpendicular to the
bottom surface 32 of the second cavity 35. The segments Y2 and Y3
are parallel to each other and perpendicular to the segments of the
first and second side walls 11 and 12. The interval D1 between the
first and second recess portions 51 and 52 or the third and fourth
recess portions 53 and 54 may be larger than the distance G1
between the first and second cavities 25 and 35. The distance G1 is
a distance between the bottom surfaces of the first and second
cavities 25 and 35.
[0085] The interval D1 between the first and second recess portions
51 and 52 or the third and fourth recess portions 53 and 54 may be
larger than the gap G0 (in FIG. 2) between the first and second
light emitting chips 71 and 72. The gap G0 is a distance between
the centers of the first and second light emitting chips 71 and
72.
[0086] Referring to FIG. 7, the distance G2 between the first
recess portion 51 and the bottom surface 22 of the first cavity 25
is equal to or different from the distance G3 between the third
recess portion 53 and the bottom surface 22 of the first cavity 25.
When the distances G2 and G3 are equal to each other, the body 10
may be prevented from warping.
[0087] Referring to FIGS. 6 and 8, the gap D3 between the lead
frames 21 and 31 and the recess portions 51 to 54 may be equal to
or larger than the thickness T1 of the lead frames 21 and 31. For
example, the gap D3 may have a width of 200 .mu.m or more. When the
gap D3 is narrower than the above range, the strength of the body
10 may be weakened.
[0088] Referring to FIGS. 6 and 9, a first outer region 11A, which
is exposed at the first side wall 11 of the body 10 between the
first and second recess portions 51 and 52, may be formed at a
second angle .theta.2 between the bottom 17 of the body 10 and the
first side wall 11 and a third angle .theta.3 different from the
second angle .theta.2. The second angle .theta.2 may be less than
90.degree. and for example, may be in the range of 60.degree. to
85.degree.. The third angle .theta.3 may be almost perpendicular to
the bottom 17 (for example, in the range of 90.degree. to
92.degree.). Thus, an inner side portion of the hanger makes tight
contact with the first and second lower regions 11A and 12A of both
side walls 11 and 12 of the body 10, so that the first lower region
11A and an upper region of the first side wall 11 may be formed at
mutually different angles. Refer to the first lower region 11A for
the second lower region 12A in the second side wall 12 of the body
10 between the third and fourth recess portions 53 and 54. The
lower regions 11A and 12A may be perpendicular to the bottom of the
body 10 and may be connected to an inclined upper region.
[0089] As described above, the recess portions 51 to 54, which are
concaved inward more than the side walls 11 and 12 of the body 10,
are formed at lower portions of the first and second side walls 11
and 12, which are long sides of the body 10, by using the inserting
protrusion of the hanger. Further, the inner side portion of the
hanger makes contact with the first and second lower regions 11A
and 12A of the first and second side walls 11 and 12 of the body
10, so that the damage of the body 10 having the length longer than
the width may be reduced. Thus, the yield of the light emitting
device 100 may be improved and the reliability of the light
emitting device 100 and the lighting system having the same may be
improved.
[0090] FIGS. 10 to 14 are views illustrating a process of
fabricating a light emitting device according to the first
embodiment. As one example, a process of fabricating a single light
emitting device will be described below.
[0091] Referring to FIG. 10, the first lead frame 21 having the
first cavity 25, the second lead frame 31 having the second cavity
35 and the connecting frame 46 are supported by press working a
metallic frame 20. Mutually different frames 21, 31 and 46 are
formed by a plurality of holes 20A in the metallic frame 20.
[0092] The metallic frame 20 includes first and second hangers 26
and 36. The first hanger 26 is disposed in one side direction of
the first and second lead frames 21 and 31, the width of the first
hanger 26 corresponds to the interval D1 of the recess portions
adjacent thereto, and the first and second inserting protrusions 27
and 28 are protruded from both ends of the first hanger 26. The
second hanger 36 is disposed in an opposite side direction of the
first and second lead frames 21 and 31, the width of the second
hanger 36 corresponds to the interval D1 of the recess portions
adjacent thereto, and the third and fourth inserting protrusions 37
and 38 are protruded from both ends of the second hanger 36.
[0093] After upper and lower molds are disposed at upper and lower
portions of the metallic frame 20, respectively, if an injection
molding is performed using a material of the body, the body 10 is
injection-molded on a predetermined region of the metallic frame 20
as shown in FIG. 11.
[0094] Referring to FIGS. 12 to 14, the inner side portion 26A of
the first hanger 26 adheres closely to the first outer region 11A
of the first side wall 11, the first inserting protrusion 27 is
inserted into the first recess portion 51, and the second inserting
protrusion 28 is inserted into the second recess portion 52. The
inner side portion 36A of the second hanger 36 adheres closely to
the second outer region 12A of the second side wall 12 of the body
10, the third inserting protrusion 37 is inserted into the third
recess portion 53, and the fourth inserting protrusion 38 is
inserted into the fourth recess portion 54.
[0095] As shown in FIG. 14, the inner side portions 26A and 36A of
the first and second hangers 26 and 36 adhere closely to the first
and second outer regions 11A and 12A of the body 10, so that the
body 10 may be prevented from being slack downwardly. Further, the
inserting protrusions 27, 28, 37 and 38 which are inserted into the
recess portions 51 to 54 support the body 10 at mutually different
positions, so that the damage of the body 10 having a long length
may be prevented.
[0096] Then, the light emitting chips are mounted on the cavities
25 and 35 of the first and second lead frames 21 and 31 and then,
are molded with a molding member after being electrically connected
through wires. Individual light emitting devices may be obtained by
cutting the above structure in units of predetermined packages.
[0097] FIGS. 15 and 16 are views showing another arrangement of the
recess portions in the light emitting device of FIG. 6.
[0098] Referring to FIG. 15, for example, the number of recess
portions 51, 52 and 55 disposed at the first side wall 1 of the
body 10 is different from the number of recess portions 53 and 54
disposed at the second side wall 12.
[0099] The fifth recess portion 55 is disposed at the first side
wall 11 between the first and second recess portions 51 and 52. An
inserting intrusion is coupled to the fifth recess portion 55. When
the body 10 is injection-molded, the inserting protrusion allows
the fifth recess portion 55 to be formed. The inserting protrusion
may support a side wall region of the body 10 at a region between
the first and second lead frames 21 and 31.
[0100] Referring to FIG. 16, the fifth and sixth recess portions 55
and 56 are provided at the central portions of the first and second
side walls 11 and 12 of the body 10. Inserting protrusions are
inserted into the fifth and sixth recess portions 55 and 56,
respectively. When the body 10 is injection-molded, the inserting
protrusions allow the fifth and sixth recess portion 55 and 56 to
be formed. The inserting protrusion may support both side wall
regions of the body 10 at a region between the first and second
lead frames 21 and 31.
[0101] FIG. 17 is a view showing a hanger position when fabricating
the light emitting device of FIGS. 15 and 16. The metallic frame 20
further includes a middle inserting protrusion 29 between the first
and second inserting protrusions 27 and 28 of the first hanger 26.
The second hanger will refer to the first hanger.
[0102] FIGS. 18 to 23 are views showing another example of the
recess portions. The recess portions will be described with
reference to the first and third recess portions. FIGS. 18 and 19
are side sectional views of a light emitting device according to
the second embodiment and show a hanger and a shape of a
recess.
[0103] Referring to FIG. 18, concave portions 51A and 53A are
formed in the first and third recess portions 51 and 53 and are
protruded in an upper direction of the body 10. The concave
portions 51A and 53A may have a polygonal shape, such as a triangle
shape, a rectangular shape or a square shape, or a semi-sphere
shape, or may include a rough structure. The height T21 of the
first and third recess portions 51 and 53 may be formed to be
thinner than the thickness of the lead frames 21 and 31.
[0104] Referring to FIG. 19, convex portions 26-1 and 37-1 are
formed in the first and third inserting protrusions 27 and 37. The
convex portions 26-1 and 37-1 are formed by etching or pressing the
upper portions of the first and second hanger 26 and 36, but the
embodiment is not limited thereto. The convex portions 26-1 and
37-1 may increase coupling with the body 10, so that the inserting
depths of the first and second inserting protrusions 27 and 37 may
be reduced.
[0105] FIGS. 20 and 21 are side sectional views of a light emitting
device according to the third embodiment and show another shape of
a recess portion and a hanger.
[0106] Referring to FIG. 20, convex portions 51B and 53B are formed
in the first and third recess portions 51 and 53 and are protruded
in a lower direction of the body 10. The convex portions 51B and
53B may have a polygonal shape, such as a triangle shape, a
rectangular shape or a square shape, or a semi-sphere shape, or may
include a rough structure such as an uneven structure. The height
of the first and third recess portions 51 and 53 may be formed to
be equal to the thickness of the lead frames 21 and 31.
[0107] Referring to FIG. 21, concave portions 26-3 and 37-2 are
formed in the first and third inserting protrusions 27 and 37. The
concave portions 26-3 and 37-2 are formed in a notch shape of the
first and second hanger 26 and 36, but the embodiment is not
limited thereto. The concave portions 26-3 and 37-2 may increase
coupling with the body 10, so that the inserting depths of the
first and third inserting protrusions 27 and 37 may be reduced.
[0108] FIGS. 22 and 23 are side sectional views of a light emitting
device according to an embodiment, and show an example of a
modified shape of a recess.
[0109] Referring to FIG. 22, the height T5 of the first and third
recess portions 51-1 and 53-1 disposed in the body 10 may be in the
range of 1/3 to 1/5 based on the thickness of the first lead frame
21, but the embodiment is not limited thereto. Refer to the above
description for the details of the second and fourth recess
portions.
[0110] Referring to FIG. 23, the first and third recess portions
51-2 and 53-2 disposed in the body 10 are protruded inward from the
first and second side walls 11 and 12 to have a sectional surface
of a triangle shape. Thus, the inserting protrusions having a
triangle shape are disposed on the side walls 11 and 12 which do
not make contact with the bottom 17 of the body 10, so that the
first and third recess portions 51-2 and 53-2 may be formed.
[0111] FIGS. 24 to 27 are rear views of a light emitting device
according to the fifth embodiment and show an example of a recess
portion having modified position and shape.
[0112] Referring to FIG. 24, the body 10 of the light emitting
device includes the recess portions 55A and 56A disposed at the
first and second side walls 11 and 12 corresponding to each other.
The recess portions 55A and 56 are disposed corresponding to each
other about the line Y0 which is perpendicular to a parallel
segment X2 at the center of the body 10. The recess portions 55A
and 56A may be disposed corresponding to a gap part which is a
region between the first and second lead frames 21 and 31.
[0113] The central line Y0 is perpendicular to the segment X2
parallel with an extending segment of the first and second side
walls 11 and 12 at the center of the body 10 and may be a line
extending through the centers of the first and second side walls 11
and 12.
[0114] The recess portions 55A and 56A are disposed corresponding
to the central line Y0 perpendicular to the center of the first
axis X of the body 10, so that, when the body is injection-molded,
the body 10 may be effectively supported in a boundary region
between the first and second lead frames 21 and 31. Thus, the
boundary region of the first and second lead frames 21 and 31,
which is a weak portion of the body 100 including a long side and a
short side, may be strengthened.
[0115] Referring to FIG. 25, the body 10 of the light emitting
device is disposed to allow the first recess portion 57 formed at
the first side wall 11 and the second recess portion 58 formed at
the second side wall 12 to cross each other. The first recess
portion 57 is disposed corresponding to the line Y2 which passes
through the center of the bottom of the first cavity of the first
lead frame 21, and the second recess portion 58 is disposed
corresponding to the line Y3 which passes through the center of the
bottom 32 of the second cavity of the second lead frame 31. In this
case, a virtual line that connects the first and second recess
portions 57 and 58 to each other may be formed at an angle in the
range of 30.degree. to 60.degree. with respect the segment Y2.
Further, the first and second recess portions 57 and 58 may be
offset from each other about a gap part which is a region between
the first and second lead frames 21 and 31.
[0116] An inserting protrusion of a hanger inserted into the first
and second recess portions 57 and 58 may support outer sides of the
first and second cavities to which the greatest load is applied
when the body is injection-molded. As shown in FIG. 10, the outer
side of the central portion of the body 10 may be supported by the
connecting frame 46, but the embodiment is not limited thereto.
[0117] Referring to FIG. 26, the body 10 of the light emitting
device is disposed to allow the first recess portion 57A formed at
the first side wall 11 and the second recess portion 58B formed at
the second side wall 12 to cross each other. The first recess
portion 57A may be disposed a region adjacent to the bottom of the
first cavity. For example, the first recess portion 57A may be
disposed between the central line Y2 perpendicular to the bottom
center of the first cavity and the central line Y0 of the body 10.
The second recess portion 58A may be disposed a region adjacent to
the bottom of the second cavity of the second lead frame 31. For
example, the second recess portion 58A may be disposed between the
central line Y3 perpendicular to the bottom center of the second
cavity and the central line Y0 of the body 10. An inserting
protrusion of a hanger inserted into the first and second recess
portions 57A and 58B may support an outer region between the first
and second cavities to which the greatest load is applied when the
body 10 is injection-molded. As shown in FIG. 10, the outer side of
the central portion of the body 10 may be supported by the
connecting frame 46, but the embodiment is not limited thereto.
[0118] Referring to FIG. 27, the light emitting device includes
first to fourth recess portions 51D, 52D, 53D and 54D which have a
semi-sphere shape and are formed at the first and second side walls
11 and 12. As another example, the shape of the first to fourth
recess portions 51D, 52D, 53D and 54D may include a triangle shape
or a stepped shape, but the embodiment is not limited thereto.
[0119] FIGS. 28 and 29 are rear views of a light emitting device
according to the sixth embodiment, and show a length of a recess
portion and a hanger.
[0120] Referring to FIG. 28, the body 10 of the light emitting
device includes the first recess portion 61 of the first side wall
11 and the second recess portion 62 of the second side wall 12
corresponding to each other. The widths W11 of the first and second
recess portions 61 and 62 may be larger than the distance G1
between the first and second cavities 25 and 35 and may be narrower
than the distance between the center lines Y2 and Y3 of the first
and second cavities 25 and 35. The width W11 may be 1/4 or more
based on the gap between the third and fourth side walls 13 and 14
of the body 10.
[0121] Referring to FIGS. 28 and 29, the inserting protrusion 39
which is the inner side portion 26A of the hanger inserted into the
first and second recess portions 61 and 62 may cover the central
regions of each side wall 11 and 12 of the body 10. The connecting
frame 46 disposed in the body 10 may be removed due to the
inserting protrusion 39 which is the inner side portion 26 of the
hanger, but the embodiment is not limited thereto. As another
embodiment, a resin material such as silicon or epoxy may be filled
in the first and second recess portions 61 and 62. The resin
material filled in the first and second recess portions 61 and 62
may strengthen the middle portion of the side walls 11 and 12.
[0122] FIGS. 30 to 32 are rear views of a light emitting device
according to the seventh embodiment, and show examples of a
modified recess.
[0123] Referring to FIG. 30, the body 10 of the light emitting
device includes the first and second recess portions 51 and 52
disposed at the first side wall 11 and the fifth recess portion 63
disposed between the first and second recess portions 51 and 52.
The fifth recess portion 63 may have a width larger than those of
the first and second recess portions 51 and 52, and may be
connected to the first and second recess portions 51 and 52. The
fifth recess portion 63 may be gradually deepened in the direction
of the central line Y0 of the body 10 or toward the centers of the
first and second side wall 11 and 12. The depth D4 of the first and
second recess portions 51 and 52 is equal to or different from the
maximum depth of the fifth recess portion 63, but the embodiment is
not limited thereto. The width of the fifth recess portion 63 may
be 1/4 based on the length of the body 10, but the embodiment is
not limited thereto.
[0124] Refer to the description of the first, second and fifth
recess portions 51, 52 and 63 for the details about the third and
fourth recess portions 53 and 54 disposed at the second side wall
12 of the body 10 and the structure of the sixth recess portion 64
between the third and fourth recess portions 53 and 54. The fifth
and sixth recess portions 63 and 64 may include a triangle shape or
a semi-sphere shape, the central portion of which is concaved in an
inner side direction of the body 10. As described in the first
embodiment, the first to fourth recess portions 51 to 54 may be
spaced apart from the third and fourth side walls 13 and 14 of the
body 10 by a predetermined distance D21.
[0125] Referring to FIG. 31, the light emitting device includes the
fifth and sixth recess portions 63A and 64A disposed at the first
and second side walls 11 and 12 of the body 10. The widths of the
fifth and sixth recess portions 63A and 64A may be 1/4 or more
based on the length of the body 10. The fifth and sixth recess
portions 63A and 64A may be spaced apart from the third and fourth
side walls 13 and 14 of the body 10 by the predetermined distance
D21, and the depths may be gradually deepened toward the central
line Y0 of the body 10. The distance D21 may be 130 .mu.m or more.
To the contrary, the maximum depth D4 of the recess portions 63A
and 64A may be formed in a region corresponding to the central
portion of the body 10 and the depth D4 may be gradually reduced
toward the third and fourth side walls 13 and 14.
[0126] Referring to FIG. 32, the light emitting device includes the
fifth and sixth recess portions 63B and 64B disposed at the first
and second side walls 11 and 12 of the body 10. The widths of the
fifth and sixth recess portions 63A and 64A may be 1/4 or more
based on the length of the body 10. The fifth and sixth recess
portions 63B and 64B may be spaced apart from the third and fourth
side walls 13 and 14 of the body 10 by the predetermined distance
D22. The distance D22 may be 130 .mu.m or more. The depths may
gradually shallow toward the center of the first and second side
walls 11 and 12 or may almost not exist at the central line Y0 of
the body 10. Thus, the minimum depth of the recess portions 63B and
64B may be formed in a region corresponding to the central portion
of the body 10 and the maximum depth D4 may be formed in a region
adjacent to the third and fourth side walls 13 and 14.
[0127] FIG. 33 is a plan view of a light emitting device according
to the eighth embodiment, and FIG. 34 is a rear view of the light
emitting device of FIG. 33.
[0128] Referring to FIGS. 33 and 34, the light emitting device 101
includes a body 110 having a concave portion 116, a first lead
frame 121 in a first region of a bottom of the concave portion 116,
a second lead frame 131 disposed in a second region of the bottom
of the concave portion 116, a gap part 119 in the bottom of the
concave portion 116 and between the first and second lead frames
121 and 131, light emitting chips 171 and 172, wires 173 to 176,
and a molding member (not shown).
[0129] The body 110 may include at least one of a resin material
such as Polyphthalamide (PPA), silicon (Si), a metallic material,
photo sensitive glass (PSG), sapphire (Al.sub.2O.sub.3), and a
printed circuit board (PCB). For example, the body 110 may include
a resin material such as Polyphthalamide (PPA), epoxy or
silicon.
[0130] An outer appearance of the body 110 may have various shapes
such as a triangle shape, a rectangular shape, a polygonal shape,
or a circular shape. The first and second lead frames 121 and 131
may be disposed on the bottom and may be mounted on a substrate as
a direct type. The first and second lead frames 121 and 131 may be
disposed at a side surface of the body 110 and may be mounted on
the substrate as an edge type. However, the embodiment is not
limited the above.
[0131] The body 110 includes a cavity having an opened upper
portion, a side surface and a bottom, and the concave portion 116
having a recess portion structure. A shape of the concave portion
116 may include a circle shape, an ellipse shape, and a polygon
shape (for example, a square shape) when viewed from the top. The
body 110 may include a plurality of side walls 111 to 114. At least
one of the side walls 111 to 114 may be perpendicular or inclined
to the bottom of the body 110. For example, a length (that is, long
length) of the first and second side walls 111 and 112 may be
longer than that (that is, short length) of the third and fourth
side walls 113 and 114. For example, the length of the first and
second side walls 111 and 112 may be two or more times longer than
that of the third and fourth side walls 113 and 114.
[0132] The first lead frame 121 is disposed in a first region of
the bottom of the concave portion 116, and the second lead frame
131 is disposed in a second region spaced apart from the first
region of the bottom of the concave portion 116. The first light
emitting chip 171 may be disposed in the first region and the
second light emitting chip 172 may be disposed in the second
region.
[0133] The lower surfaces of the first and second lead frames 121
and 131 may be exposed to the bottom of the body 110 and may be
disposed on the same plane with the bottom of the body 110.
[0134] The gap part 119 between the first and second frames 121 and
131 may be obliquely disposed. A central portion of the gap part
119 may be formed in a stepped structure. Since the gap part 119
may be formed in the diagonal form, the strength of the boundary
portion between the first and second frames 121 and 131 may be
enhanced.
[0135] A first lead part 123 of the first lead frame 121 may be
disposed on the bottom of the body 110 and may be protruded toward
the third side wall 113. A second lead part 133 of the second lead
frame 131 may be disposed on the bottom of the body 110 and may be
protruded toward the fourth side wall 114. Refer to the first
embodiment for a material and thickness of the first and second
lead frames 121 and 131.
[0136] As shown in FIGS. 33 and 34, the first and second lead
frames 121 and 131 have no cavity structure. The lower surfaces of
the first and second lead frames 121 and 131 are flat. That is, the
entire lower surfaces of the first and second lead frames 121 and
131 may be disposed on the same plane. The thickness of the light
emitting device 101 may be thinly provided by removing the cavity
structure from the first and second lead frames 121 and 131.
[0137] The first side wall 111 of the body 110 includes the first
and second recess portions 151 and 152, and the second side wall
112 includes the third and fourth recess portions 153 and 154.
[0138] An inner width W2 of the first to fourth recess portions 151
to 154 may be narrower than an outer width W3 thereof. The inner
portion of the first to fourth recess portions 151 to 154 may be
directed to an inner side of the body 110 and the outer portion
thereof may be directed to the side wall of the body.
[0139] The depth T6 of the first to fourth recess portions 151 to
154 may be formed in the range of 30 .mu.m to 130 .mu.m, but the
embodiment is not limited thereto. The first to fourth recess
portions 151 to 154 may be spaced apart from each other such that
the distance D6 from the outmost second or fourth side wall 113 or
114 may be 130 .mu.m or more.
[0140] The inserting protrusion of the hanger inserted into the
first to fourth recess portions 151 to 154 may be formed in a shape
having a large inner width and a narrow outer width, so that the
body may be effectively supported by the structure of the inserting
protrusion.
[0141] The first light emitting chip 171 may be disposed over the
first lead frame 121 and the second light emitting chip 172 may be
disposed over the second lead frame 131. The first light emitting
chip 171 is connected to the first lead frame 121 through the first
wire 173 and is connected to the second lead frame 131 through the
second wire 174. The second light emitting chip 172 is disposed
over the second lead frame 131. The second light emitting chip 172
is connected to the second lead frame 131 through the third wire
175 and is connected to the first lead frame 121 through the fourth
wire 176. The gap part 119 may be disposed is disposed in a
diagonal form, so that the second and fourth wires 174 and 176 may
be provided in the shortest length.
[0142] Referring to FIG. 35, the first side wall 111 of the body
110 includes the fifth recess portion 161. The fifth recess portion
161 may be spaced apart from the third and fourth side walls 113
and 114 by a distance of 130 .mu.m or more or for example, 200
.mu.m or more. The second side wall 112 of the body 110 includes
the sixth recess portion 162. The sixth recess portion 162 has
almost the same width as that of the fifth recess portion 161 and
is spaced apart from the third and fourth side walls 113 and
114.
[0143] The fifth and sixth recess portions 161 and 162 may have a
width which is 1/4 or more based on the length of the body 110, but
the embodiment is not limited thereto. The longitudinal direction
of the body 110 may pass through the centers of the light emitting
chips 171 and 172 shown in FIG. 33.
[0144] The fifth and sixth recess portions 161 and 162 may be
spaced apart from the first and second lead frames 121 and 131 by
200 .mu.m or more. In this case, when the gap between the fifth and
sixth recess portions 161 and 162 and the first and second lead
frames 121 and 131 is narrow, the strength of the body may be not
sufficiently obtained due to the narrow gap.
[0145] Referring to FIG. 36, the first and second recess portions
163 and 164 are disposed in the first side wall 111 of the body
110, and the fifth recess portion 161A is disposed between the
first and second recess portions 163 and 164. The fifth recess
portion 161A has a width corresponding to a gap between the first
and second recess portions 163 and 164, and may be connected to the
first and second recess portions 163 and 164. The fifth recess
portion 161A may have a width gradually increased or decreased from
the first and second recess portions 163 and 164 to the central
line Y0 of the body 100, but the embodiment is not limited
thereto.
[0146] The third and fourth recess portions 165 and 166 are
disposed in the second side wall 112 of the body 110 and the sixth
recess portion 162A is disposed between the third and fourth recess
portions 165 and 166. Refer to the first, second and fifth recess
portions 163, 164 and 161A for the structures of the third, fourth
and sixth recess portions 165, 166 and 162A.
[0147] Referring to FIG. 37, the fifth recess portion 161 C is
formed in the first side wall 111 of the body 110 and the sixth
recess portion 162C is formed in the second side wall 112. The
centers of the fifth and sixth recess portions 161C and 162C are
positioned at the center of the body 110 and the widths of the
fifth and sixth recess portions 161C and 162C may be 1/4 or more
based on the length of the body 110. Refer to the structures of the
recess portions in the first embodiment for the depth of the fifth
and sixth recess portions 161C and 162C.
[0148] The seventh recess portion 161D is formed in the fifth
recess portion 161C. The seventh recess portion 161D may have a
width narrower than that of the fifth recess portion 161C, for
example, in the range of 50 .mu.m to 200 .mu.m, and have a depth
from the fifth recess portion 161C in the range of 10 .mu.m to 50
.mu.m. The seventh recess portion 161D may be disposed
corresponding to the gap part 119 between the first and second lead
frames 121 and 131.
[0149] The eighth recess portion 162D is formed in the sixth recess
portion 162C. The eighth recess portion 162D may have a width
narrower than that of the sixth recess portion 162C, for example,
in the range of 50 .mu.m to 200 .mu.m, and have a depth from the
sixth recess portion 162C in the range of 10 .mu.m to 50 .mu.m. The
eighth recess portion 162D may be disposed corresponding to the gap
part 119 between the first and second lead frames 121 and 131.
Thus, the gap G4 between the lines perpendicular to the seventh and
eighth recess portions 161D and 162D spaced apart from each other
may be 30 .mu.m or more, but the embodiment is not limited
thereto.
[0150] FIG. 38 is a plan view of a light emitting device according
to the ninth embodiment. In the description of the ninth
embodiment, the same configurations as those of FIG. 38 refer to
FIG. 33 and the first embodiment.
[0151] Referring to FIG. 38, the first to fourth recess portions
151A to 154A are formed in the first and second side walls 111 and
112 of the body 110. This structure may be selectively applied to
the above-described embodiments, but the embodiment is not limited
thereto.
[0152] The connecting frame 146 is disposed between the first and
second lead frames 121 and 131 in the body 110. The connecting
frame 146, which is disposed between the first and second lead
frames 121 and 131, serves as a middle connecting terminal.
[0153] FIG. 39 is a plan view of a light emitting device according
to the tenth embodiment. FIG. 40 is a rear view of the light
emitting device of FIG. 39. FIG. 41 is a side sectional view of the
light emitting device of FIG. 39.
[0154] Referring to FIG. 39, the light emitting device 200 includes
a body 210 having a concave portion 216, first and second lead
frames 221 and 231 in the concave portion 216, light emitting chips
271 and 272, wires 273 to 275 and a molding member 240.
[0155] The first lead frame 221 includes a first lead part 223
disposed in the third side wall 213 of the body 210 and a second
lead part 233 disposed in the fourth side wall 214.
[0156] The second lead frame 231 may be longer than that of the
first lead frame 221 and for example, may be 1/2 based on the
length of the body 110.
[0157] The first and second light emitting chips 271 and 272 are
disposed on the second lead frame 231. The first light emitting
chip 271 is connected to the first lead frame 221 through the wire
273 and is connected to the second light emitting chip 272 through
the wire 274. The second light emitting chip 272 may be connected
to the second lead frame 231 through the wire 275.
[0158] Referring to FIGS. 40 and 41, a plurality of recess
portions, for example, two recess portions or more may be disposed
in the first side wall 211 of the body 210. For example, the first
to fourth recess portions 251 to 254 are disposed in the first side
wall 211. The plurality of recess portions, for example, two recess
portions or more may be disposed in the second side wall 212. For
example, the fifth to eighth recess portions 255, 256, 257 and 258
are disposed in the second side wall 212. However, the embodiment
is not limited the above.
[0159] The first to fourth recess portions 251, 252, 253 and 254
correspond to the fifth to eighth recess portions 255, 256, 257 and
258, respectively. In this case, they may be disposed symmetrically
to each other about the longitudinal direction of the body 210.
[0160] The first to fourth recess portions 251, 252, 253 and 254
and the fifth to eighth recess portions 255, 256, 257 and 258 may
be spaced apart from the third and fourth side walls 213 and 214 by
a predetermined distance D2. Refers to the first embodiment for the
distance D2.
[0161] The intervals D11 and D12 between the neighbor recess
portions among the first to fourth recess portions 251, 252, 253
and 254 may be different from each other. For example, the interval
D11 between the outermost first and fourth recess portions 251 and
254 and the second and third recess portions 252 and 253 adjacent
to the first and fourth recess portions 251 and 254 may be equal to
each other, and the interval D12 between the second and third
recess portions 252 and 253 may be larger than the interval D11.
The positions of the first to eighth recess portions 251 to 258 may
be configured by taking into consideration the length difference
between the first and second lead frames 221 and 231 and the
boundary regions of the first and second lead frames.
[0162] The embodiment may prevent the body from being damaged when
the light emitting device is injection-molded, and may provide the
light emitting device having the recess portions which can support
the body coupled to the cavities of the lead frames. According to
the embodiment, the yield rate and the reliability of the light
emitting device may be improved. The embodiment can improve the
reliability of the light emitting device and a lighting apparatus
having the same.
[0163] FIG. 42 is a side sectional view showing one example of the
light emitting chip according to the embodiment.
[0164] Referring to FIG. 42, the light emitting chip 71 includes a
substrate 311, a buffer layer 312, a light emitting structure 310,
a first electrode 316, and a second electrode 317. The substrate
311 may include a substrate including a transmissive material or a
non-transmissive material, and may include a conductive substrate
or an insulating substrate.
[0165] The buffer layer 312 reduces the lattice constant difference
between the materials constituting the substrate 311 and the light
emitting structure 310, and may include a nitride semiconductor. A
nitride semiconductor layer, which is not doped with dopants, is
further disposed between the buffer layer 312 and the light
emitting structure 310, so that the crystal quality can be
improved.
[0166] The light emitting structure 310 includes a first conductive
semiconductor layer 313, an active layer 314, and a second
conductive semiconductor layer 315.
[0167] The first conductive semiconductor layer 313 may include the
group III-V compound semiconductor doped with the first conductive
dopant. For example, the first conductive semiconductor layer 313
may include the semiconductor material having the compositional
formula of InxAlyGa1-x-yN (0.ltoreq.x.ltoreq.1,
0.ltoreq.y.ltoreq.1, 0.ltoreq.x+y.ltoreq.1). In detail, the first
conductive semiconductor layer 313 may include the stack structure
of layers including one selected from the group consisting of GaN,
InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP,
and AlGaInP. If the first conductive semiconductor layer 313 is an
n type semiconductor layer, the first conductive dopant includes
the n type dopant such as Si, Ge, Sn, Se, or Te.
[0168] A first clad layer may be formed between the first
conductive semiconductor layer 313 and the active layer 314. The
first clad layer may include a GaN-based semiconductor, and the
bandgap of the first clad layer may be equal to or greater than the
bandgap of the active layer 314. The first clad layer has the first
conductive type, and confines carriers.
[0169] The active layer 314 is disposed on the first conductive
semiconductor layer 313, and includes a single quantum well
structure, a multiple quantum well (MQW) structure, a quantum wire
structure or a quantum dot structure. The active layer 314 has the
cycle of the well and barrier layers. The well layer may have the
composition formula of InxAlyGa1-x-yN (0.ltoreq.x.ltoreq.1,
0.ltoreq.y.ltoreq.1, 0.ltoreq.x+y.ltoreq.1), and the barrier layer
may have the composition formula of InxAlyGa1-x-yN
(0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, 0.ltoreq.x+y.ltoreq.1).
At least one cycle of the well/barrier layers may be used through
the stack structure of InGaN/GaN, GaN/AlGaN, InGaN/AlGaN,
InGaN/InGaN, InAlGaN/AlGaN and InAlGaN/InAlGaN. The barrier layer
may include a semiconductor material having the bandgap higher than
the bandgap of the well layer.
[0170] The second conductive semiconductor layer 315 is formed on
the active layer 314. The second conductive semiconductor layer 315
includes a semiconductor doped with second conductive dopants, for
example, includes a semiconductor having the composition formula of
InxAlyGa1-x-yN (0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1,
0.ltoreq.x+y.ltoreq.1). In detail, the second conductive
semiconductor layer 315 may include one selected from compound
semiconductors such as GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN,
AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. If the second conductive
semiconductor layer 315 is a p type semiconductor layer, the
semiconductor conductive dopant includes the p type dopant such as
Mg, Zn, Ca, Sr, or Ba.
[0171] The second conductive semiconductor layer 315 may include a
superlattice structure, and the superlattice structure may include
an InGaN/GaN superlattice structure or am AlGaN/GaN superlattice
structure. The superlattice structure of the second conductive
semiconductor layer 315 abnormally spreads the current, thereby
protecting the active layer 314.
[0172] In addition, the light emitting structure 310 may have an
opposite conductive type. For example, the first conductive
semiconductor layer 313 may include a P type semiconductor layer,
and the second conductive semiconductor layer 315 may include an N
type semiconductor layer. The second conductive semiconductor layer
315 may be disposed thereon with a first conductive semiconductor
layer having the polarity opposite to the second conductive type
polarity.
[0173] The light emitting structure 310 may be realized by using
one of an n-p junction structure, a p-n junction structure, an
n-p-n junction structure, and a p-n-p junction structure. The "p"
represents a p type semiconductor, the "n" represents an n type
semiconductor layer, and the "-" represents that the p type
semiconductor is directly or indirectly connected to the n type
semiconductor. Hereinafter, a case that the uppermost layer of the
light emitting structure 310 is the second conductive semiconductor
layer 315 will be described for the convenience of explanation.
[0174] The first electrode 316 is disposed on the first conductive
semiconductor layer 313, and the second electrode 317 having a
current spreading layer is disposed on the second conductive
semiconductor layer 315. The first and second electrodes 316 and
317 are connected to each other through a wire, or through another
connection scheme.
[0175] FIG. 43 is a graph showing another example of the light
emitting chip according to the embodiment. Hereinafter, in the
following description of the embodiment, the details of the same
parts as that of FIG. 42 will be omitted except for brief
description.
[0176] Referring to FIG. 43, in a light emitting chip 71A according
to the embodiment, a contact layer 321 is formed under a light
emitting structure 310, a reflective layer 324 is formed under the
contact layer 321, a support member 325 is formed under the
reflective layer 324, and a protective layer 323 may be formed
around the reflective layer 324 and the light emitting structure
310.
[0177] One or a plurality of first electrodes 316 may be formed on
the light emitting structure 310, and the first electrode 316
includes a pad bonded to a wire.
[0178] The light emitting chip may be formed by removing a growth
substrate after forming a contact layer 321, a protective layer
323, a reflective layer 324, and a support member 323 under the
second conductive semiconductor layer 315.
[0179] The contact layer 321 may make ohmic-contact with a lower
layer of the light emitting structure 310, for example, the second
conductive semiconductor layer 315, and may include a metallic
oxide, a metallic nitride, an insulating material, or a conductive
material. For example, the contact layer 321 may include ITO
(indium tin oxide), IZO (indium zinc oxide), IZTO (indium zinc tin
oxide), IAZO (indium aluminum zinc oxide), IGZO (indium gallium
zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zinc
oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), Ag, Ni,
Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, and the selective
combination thereof. The contact layer 321 may be formed in a
multi-layer structure by using a metallic material and a
transparent material such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, or
ATO. For example, the contact layer 321 may have the stack
structure of IZO/Ni, AZO/Ag, IZO/Ag/Ni, or AZO/Ag/Ni. A layer to
block current may be further formed in the contact layer 321
corresponding to the electrode 316.
[0180] The protective layer 323 may include a metallic oxide or an
insulating material. For example, the protective layer 323 may
selectively include ITO (indium tin oxide), IZO (indium zinc
oxide), IZTO (indium zinc tin oxide), IAZO (indium aluminum zinc
oxide), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin
oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO
(gallium zinc oxide), SiO2, SiOx, SiOxNy, Si3N4, Al2O3, or TiO2.
The protective layer 323 may be formed through a sputtering scheme
or a deposition scheme. The metal constituting the reflective layer
324 may prevent the layers of the light emitting structure 310 from
being shorted.
[0181] The reflective layer 324 may include metal such as Ag, Ni,
Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, or the selective
combination thereof. The reflective layer 324 may have a width
greater than the width of the light emitting structure 310, thereby
improving the light reflection efficiency. A metallic layer for
bonding and a metallic layer for thermal diffusion may be further
disposed between the reflective layer 324 and the support member
325, but the embodiment is not limited thereto.
[0182] The support member 325 serves as a base substrate, and may
include metal such as Cu, Au, Ni, Mo, or Cu--W, and a carrier
wafer, such as Si, Ge, GaAs, ZnO, and SiC. An adhesive layer may be
further formed between the support member 325 and the reflective
layer 324, and bonds the two layers to each other. The disclosed
light emitting chip is four the illustrative purpose, and the
embodiment is not limited thereto. The light emitting chip may be
selective applied to the light emitting device according to the
embodiment, but the embodiment is not limited thereto.
[0183] <Lighting System>
[0184] The light emitting device according to the embodiment is
applicable to a lighting system. The lighting system includes a
structure in which plurality of light emitting devices are arrayed.
The lighting system includes a display apparatus shown in FIGS. 44
and 45, a lighting apparatus shown in FIGS. 46 to 50, a lighting
lamp, a camera flash, a signal lamp, a headlamp for a vehicle, and
an electronic display.
[0185] FIG. 44 is an exploded perspective view showing a display
apparatus having the light emitting device according to the
embodiment.
[0186] Referring to FIG. 44, a display apparatus 1000 according to
the embodiment includes a light guide plate 1041, a light source
module 1033 to supply light to the light guide plate 1041, a
reflective member 1022 under the light guide plate 1041, an optical
sheet 1051 on the light guide plate 1041, a display panel 1061 on
the optical sheet 1051, and a bottom cover 1011 to receive the
light guide plate 1041, the light source module 1033, and the
reflective member 1022, but the embodiment is not limited
thereto.
[0187] The bottom cover 1011, the reflective sheet 1022, the light
guide plate 1041, the optical sheet 1051, and the light unit 1050
may be defined as a light unit 1050.
[0188] The light guide plate 1041 diffuses the light supplied from
the light source module 1033 to provide surface light. The light
guide plate 1041 may include a transparent material. For example,
the light guide plate 1041 may include one of acryl-based resin,
such as PMMA (polymethyl methacrylate, PET (polyethylene
terephthalate), PC (polycarbonate), COC (cyclic olefin copolymer)
and PEN (polyethylene naphtha late) resin.
[0189] The light source module 1033 is disposed on at least one
side of the light guide plate 1041 to supply the light to at least
one side of the light guide plate 1041. The light source module
1033 serves as the light source of the display device.
[0190] At least one light source module 1033 is disposed to
directly or indirectly supply the light from one side of the light
guide plate 1041. The light source module 1033 may include a board
1031 and the light emitting device according to the embodiments or
the light emitting device 100. The light emitting device or the
light emitting device 100 are arranged on the board 1031 while
being spaced apart from each other at the predetermined
interval.
[0191] The board 1031 may include a printed circuit board (PCB)
including a circuit pattern (not shown). In addition, the board
1031 may also include a metal core PCB (MCPCB) or a flexible PCB
(FPCB) as well as a typical PCB, but the embodiment is not limited
thereto. If the light emitting device 100 is installed on the side
of the bottom cover 1011 or on a heat dissipation plate, the board
1031 may be omitted. The heat dissipation plate partially makes
contact with the top surface of the bottom cover 1011.
[0192] In addition, the light emitting device 100 are arranged such
that light exit surfaces to discharge light of the light emitting
device 100 are spaced apart from the light guide plate 1041 by a
predetermined distance on the board 1031, but the embodiment is not
limited thereto. The light emitting device 100 may directly or
indirectly supply the light to a light incident surface, which is
one side of the light guide plate 1041, but the embodiment is not
limited thereto.
[0193] The reflective member 1022 is disposed below the light guide
plate 1041. The reflective member 1022 reflects the light, which is
traveled downward through the bottom surface of the light guide
plate 1041, toward the display panel 1061, thereby improving the
brightness of the light unit 1050. For example, the reflective
member 1022 may include PET, PC or PVC resin, but the embodiment is
not limited thereto. The reflective member 1022 may serve as the
top surface of the bottom cover 1011, but the embodiment is not
limited thereto.
[0194] The bottom cover 1011 may receive the light guide plate
1041, the light source module 1033, and the reflective member 1022
therein. To this end, the bottom cover 1011 has a receiving section
1012 having a box shape with an opened top surface, but the
embodiment is not limited thereto. The bottom cover 1011 can be
coupled with the top cover (not shown), but the embodiment is not
limited thereto.
[0195] The bottom cover 1011 can be manufactured through a press
process or an extrusion process by using metallic material or resin
material. In addition, the bottom cover 1011 may include metal or
non-metallic material having superior thermal conductivity, but the
embodiment is not limited thereto.
[0196] The display panel 1061, for example, is an LCD panel
including first and second transparent substrates, which are
opposite to each other, and a liquid crystal layer interposed
between the first and second substrates. A polarizing plate can be
attached to at least one surface of the display panel 1061, but the
embodiment is not limited thereto. The display panel 1061 displays
information by allowing the light to pass therethrough. The display
device 1000 can be applied to various portable terminals, monitors
of notebook computers, monitors or laptop computers, and
televisions.
[0197] The optical sheet 1051 is disposed between the display panel
1061 and the light guide plate 1041 and includes at least one
transmissive sheet. For example, the optical sheet 1051 includes at
least one selected from the group consisting of a diffusion sheet,
a horizontal and vertical prism sheet, and a brightness enhanced
sheet. The diffusion sheet diffuses the incident light, the
horizontal and vertical prism sheet concentrates the incident light
onto the display panel 1061, and the brightness enhanced sheet
improves the brightness by reusing the lost light. In addition, a
protective sheet can be disposed on the display panel 1061, but the
embodiment is not limited thereto.
[0198] The light guide plate 1041 and the optical sheet 1051 can be
disposed in the light path of the light source module 1033 as
optical members, but the embodiment is not limited thereto.
[0199] FIG. 45 is a sectional view showing a display apparatus
according to the embodiment.
[0200] Referring to FIG. 45, the display device 1100 includes a
bottom cover 1152, a board 100 on which the light emitting device
100 are arrayed, an optical member 1154, and a display panel
1155.
[0201] The board 100 and the light emitting device 100 may
constitute the light source module 1160. In addition, the bottom
cover 1152, at least one light source module 1160, and the optical
member 1154 may constitute the light unit. The bottom cover 1151
can be disposed with a receiving section 1153, but the embodiment
is not limited thereto. The light source module 1160 includes a
board 100, and a plurality of light emitting devices arranged on
the board 100 or a light emitting device 100.
[0202] The optical member 1154 may include at least one selected
from the group consisting of a lens, a light guide plate, a
diffusion sheet, a horizontal and vertical prism sheet, and a
brightness enhanced sheet. The light guide plate may include PC or
PMMA (Poly methyl methacrylate). The light guide plate can be
omitted. The diffusion sheet diffuses the incident light, the
horizontal and vertical prism sheet concentrates the incident light
onto a display region, and the brightness enhanced sheet improves
the brightness by reusing the lost light.
[0203] The optical member 1154 is disposed above the light source
module 1160 in order to convert the light emitted from the light
source module 1160 into the surface light.
[0204] FIGS. 46 to 48 are views showing a lighting apparatus
according to the embodiment.
[0205] FIG. 46 is a perspective view of the lighting apparatus
according to the embodiment when viewed from the top, FIG. 47 is a
perspective view of the lighting apparatus depicted in FIG. 46 when
viewed from the bottom, and FIG. 48 is an exploded perspective view
of the lighting apparatus depicted in FIG. 46.
[0206] Referring to FIGS. 46 to 48, the lighting apparatus
according to the embodiment may include a cover 2100, a light
source module 2200, a radiator 2400, a power supply part 2600, an
inner case 2700, and a socket 2800. The lighting apparatus
according to the embodiment may further include at least one of a
member 2300 and a holder 2500. The light source module 2200 may
include the light emitting device or the light emitting device
package according to the embodiment.
[0207] For example, the cover 2100 may have a blub shape, a
hemisphere shape, a partially-open hollow shape. The cover 2100 may
be optically coupled with the light source module 2200. For
example, the cover 2100 may diffuse, scatter, or excite light
provided from the light source module. The cover 2100 may be a type
of optical member. The cover 2100 may be coupled with the radiator
2400. The cover 2100 may include a coupling part which is coupled
with the radiator 2400.
[0208] The cover 2100 may include an inner surface coated with a
milk-white paint. The milk-white paint may include a diffusion
material to diffuse light. The cover 2100 may have the inner
surface of which surface roughness is greater than that of the
outer surface thereof. The surface roughness is provided for the
purpose of sufficiently scattering and diffusing the light from the
light source module 2200.
[0209] For example, a material of the cover 2100 may include glass,
plastic, polypropylene (PP), polyethylene (PE), and polycarbonate
(PC). The polycarbonate (PC) has the superior light resistance,
heat resistance and strength among the above materials. The cover
2100 may be transparent so that a user may view the light source
module 2200 from the outside, or opaque. The cover 2100 may be
formed through a blow molding scheme.
[0210] The light source module 2200 may be disposed at one surface
of the radiator 2400. Accordingly, the heat from the light source
module 2200 is transferred to the radiator 2400. The light source
module 2200 may include a light source 2210, a connection plate
2230, and a connector 2250.
[0211] The member 3100 is disposed at a top surface of the radiator
2400, and includes guide grooves 2310 into which a plurality of
light sources 2210 and the connector 2250 are inserted. The guide
grooves 2310 correspond to a substrate of the light source 2210 and
the connector 2250.
[0212] A surface of the member 2300 may be coated with a light
reflective material. For example, the surface of the member 2300
may be coated with white paint. The member 2300 again reflects
light, which is reflected by the inner surface of the cover 2100
and is returned to the direction of the light source module 2200,
to the direction of the cover 2100. Accordingly, the light
efficiency of the lighting system according to the embodiment may
be improved.
[0213] For example, the member 2300 may include an insulating
material. The connection plate 2230 of the light source module 2200
may include an electrically conductive material. Accordingly, the
radiator 2400 may be electrically connected to the connection plate
2230. The member 2300 may be configured by an insulating material,
thereby preventing the connection plate 2230 from being
electrically shorted with the radiator 2400. The radiator 2400
receives heat from the light source module 2200 and the power
supply part 2600 and radiates the heat.
[0214] The holder 2500 covers a receiving groove 2719 of an
insulating part 2710 of an inner case 2700. Accordingly, the power
supply part 2600 received in the insulating part 2710 of the inner
case 2700 is closed. The holder 2500 includes a guide protrusion
2510. The guide protrusion 2510 has a hole through a protrusion
2610 of the power supply part 2600.
[0215] The power supply part 2600 processes or converts an electric
signal received from the outside and provides the processed or
converted electric signal to the light source module 2200. The
power supply part 2600 is received in the receiving groove of the
inner case 2700, and is closed inside the inner case 2700 by the
holder 2500.
[0216] The power supply part 2600 may include a protrusion 2610, a
guide part 2630, a base 2650, and an extension part 2670.
[0217] The guide part 2630 has a shape protruding from one side of
the base 2650 to the outside. The guide part 2630 may be inserted
into the holder 2500. A plurality of components may be disposed
above one surface of the base 2650. For example, the components may
include a DC converter converting AC power provided from an
external power supply into DC power, a driving chip controlling
driving of the light source module 2200, and an electrostatic
discharge (ESD) protection device protecting the light source
module 2200, but the embodiment is not limited thereto.
[0218] The extension part 2670 has a shape protruding from an
opposite side of the base 2650 to the outside. The extension part
2670 is inserted into an inside of the connection part 2750 of the
inner case 2700, and receives an electric signal from the outside.
For example, a width of the extension part 2670 may be smaller than
or equal to a width of the connection part 2750 of the inner case
2700. First terminals of a "+ electric wire" and a "- electric
wire" are electrically connected to the extension part 2670 and
second terminals of the "+ electric wire" and the "- electric wire"
may be electrically connected to a socket 2800.
[0219] The inner case 2700 may include a molding part therein
together with the power supply part 2600. The molding part is
prepared by hardening molding liquid, and the power supply part
2600 may be fixed inside the inner case 2700 by the molding
part.
[0220] FIGS. 49 and 50 are views showing other examples of a
lighting apparatus according to the embodiment.
[0221] FIG. 49 is a perspective view showing the lighting apparatus
according to the embodiment, and FIG. 50 is an exploded perspective
view of the lighting apparatus shown in FIG. 49.
[0222] Referring to FIGS. 49 and 50, the lighting apparatus
according to the embodiment may include a cover 3100, a light
source part 3200, a radiator 3300, a circuit part 3400, an inner
case 3500, and a socket 3600. The light source part 3200 may
include the light emitting device or the light emitting device
module according to the embodiment.
[0223] The cover 3100 may have a blub shape and is hollow. The
cover 3100 has an opening 3110. The light source part 3200 and a
member 3350 may be inserted through the opening 3110.
[0224] The cover 3100 may be coupled with the radiator 3300, and
may surround the light source part 3200 and the member 3350. The
light source part 3200 and the member 3350 may be blocked from the
outside by the coupling between the cover 3100 and the radiator
3300. The cover 3100 may be coupled with the radiator 3300 by an
adhesive or various schemes such as a rotation coupling scheme and
a hook coupling scheme. The rotation coupling scheme is a scheme
where a thread of the cover 3100 is coupled with a screw groove of
the radiator 3300, and the cover 3100 is coupled with the radiator
3300 by rotation of the cover 3100. The hook coupling scheme is a
scheme where a projection of the cover 3100 is inserted into a
groove of the radiator 3300 so that the cover 3100 is coupled with
the radiator 3300.
[0225] The cover 3100 may be optically coupled with the light
source part 3200. In detail, the cover 3100 may diffuse, scatter,
or excite light provided from a light emitting device 3230 of the
light source part 3200. The cover 3100 may be a type of optical
member. The cover 3100 may be provided at an inner/outer surface or
an inside thereof with a luminescence material in order to excite
the light supplied from the light source part 3200.
[0226] The cover 3100 may include an inner surface coated with a
milk-white paint. The milk-white paint may include a diffusion
material to diffuse light. The cover 3100 may have the inner
surface of which surface roughness is greater than that of the
outer surface thereof. The surface roughness is provided for the
purpose of sufficiently scattering and diffusing the light from the
light source part 3200.
[0227] For example, a material of the cover 3100 may include glass,
plastic, polypropylene (PP), polyethylene (PE), and polycarbonate
(PC). The polycarbonate (PC) has the superior light resistance,
heat resistance and strength among the above materials. The cover
3100 may be transparent so that a user may view the light source
module 2200 from the outside, or opaque. The cover 3100 may be
formed through a blow molding scheme.
[0228] The light source part 3200 is disposed at the member 3350 of
the radiator 3300, and a plurality of light source part may be
disposed. In detail, the light source part 3200 may be disposed in
at least one of a plurality of lateral sides of the member 3350. A
top end of the light source part 3200 of the light source part 3200
may be disposed at the lateral side of the member 3350.
[0229] The light source part 3200 may be disposed at three of six
lateral sides of the member 3350. However, the embodiment is not
limited thereto, and the light source part 3200 may be disposed at
all lateral sides of the member 3350. The light source part 3200
may include a substrate 3210 and a light emitting device 3230. The
light emitting device 32030 may be disposed on one surface of the
substrate 3210.
[0230] The substrate 3210 has a rectangular shape, but the
embodiment is not limited thereto. The substrate 3210 may have
various shapes. For example, the substrate 3210 may have a circular
shape or a polygonal shape. The substrate 3210 may be provided by
printing a circuit pattern on an insulator. For example, the
typical printed circuit board (PCB) may include a metal core PCB, a
flexible PCB, and a ceramic PCB. In addition, the substrate may
have a COB (chips on board) type in which LED chips, which are not
packaged, are directly bonded on the PCB. In addition, the
substrate 3210 may include a material to effectively reflect light,
or the surface of the substrate may have a color such as a gold
color or a silver color to effectively reflect the light. The
substrate 3210 may be electrically connected to the circuit part
3400 received in the radiator 3300. For example, the substrate 3210
and the circuit part 3400 may be connected to each other by a wire.
The wire may connect the substrate 3210 and the circuit part 3400
to each other through the radiator 3300.
[0231] The light emitting device 3230 may include a light emitting
diode chip to emit red, green, and blue lights or a light emitting
diode chip to emit UV. The light emitting diode may have the
lateral type or the vertical type. The light emitting diode may
emit one of blue, red, yellow, and green lights.
[0232] The light emitting device 3230 may include a luminescence
material. The luminescence material may include at least one of
garnet-based phosphors (YAG, or TAG), silicate-based phosphors,
nitride-based phosphors, and oxynitride-based phosphors. The
luminescence material may include at least one of a red
luminescence material, a yellow luminescence material and a green
luminescence material.
[0233] The radiator 3300 is coupled with the cover 3100, and may
radiate heat from the light source part 3200. The radiator 330 has
a predetermined volume, and includes a top surface 3310 and a
lateral side 3330. The member 3350 may be disposed on the top
surface 3310 of the radiator 3310. The top surface 3310 of the
radiator 3300 may be coupled with the cover 3100. The top surface
3310 of the radiator 3300 may have a shape corresponding to an
opening 3110 of the cover 3100.
[0234] A plurality of heat radiation pins 3370 may be disposed at
the lateral side 3330 of the radiator 3300. The heat radiation pin
3370 may extend outward from the lateral side of the radiator 3300
or may be connected to the lateral side of the radiator 3300. The
heat radiation pin 3370 may improve heat radiation efficiency by
increasing a heat radiation area of the radiator 3300. The lateral
side 3330 may not include the heat radiation pin 3370.
[0235] The member 3350 may be disposed on the top surface of the
radiator 3300. The member 3350 may be integrated with or coupled to
the top surface 3310 of the radiator 3300. The member 3350 may have
the shape of a polygonal prism. In detail, the member 3350 may have
the shape of a hexagonal prism. The member 3350 having the shape of
a hexagonal prism includes a top surface, a bottom surface, and six
lateral sides. The member 3350 may have the shape of a circular
prism or the shape of an elliptical prism as well as the shape of a
hexagonal prism. When the member 3350 has the shape of a circular
prism or the shape of an elliptical prism, the substrate 3210 of
the light source part 3200 may be a flexible substrate.
[0236] The light source part 3200 may be disposed at six lateral
sides of the member 3350. The light source part 3200 may be
disposed at all or some of the six lateral sides of the member
3350. For example, the light source part 3200 is disposed at three
of the six lateral sides of the member 3350.
[0237] The substrate 3210 is disposed at the lateral side of the
member 3350. The lateral side of the member 3350 may be
substantially vertical to the top surface of the radiator 3300.
Accordingly, the substrate 3210 and the top surface of the radiator
3300 may be substantially vertical to each other.
[0238] The member 3350 may include a material representing thermal
conductivity. Thus, heat from the light source part 3200 can be
rapidly transferred to the member 3350. For example, the material
for the member 3350 may include an alloy of metals such as aluminum
(Al), nickel (Ni), copper (Cu), magnesium (Mg), silver (Ag), or tin
(Sn). The member 3350 may include a plastic material having thermal
conductivity. The plastic material having thermal conductivity is
lighter than the metal and has thermal conductivity in a single
direction.
[0239] The circuit part 3400 receives power from the outside, and
converts the received power suitably for the light source part
3200. The circuit part 3400 provides the converted power to the
light source part 3200. The circuit part 3400 may be disposed at
the radiator 3300. In detail, the circuit part 3400 may be received
in the inner case 3500, and may be received in the radiator 3300
together with the inner case 3500. The circuit part 3400 may
include a circuit board 3410 and a plurality of components mounted
on the circuit board 3410.
[0240] The circuit board 3410 has a circular shape, but the
embodiment is not limited thereto. That is, the circuit board 3410
may have various shapes. For example, the circuit board may have an
elliptical shape or a polygonal shape. The circuit board 3410 may
be provided by printing a circuit pattern on an insulator. The
circuit board 3410 is electrically connected to the substrate 3210
of the light source part 3200. For example, the circuit part 3410
and the substrate 3210 may be connected to each other by a wire.
The wire may be disposed inside the radiator 3300 to connect the
substrate 3210 with the circuit board 3410. For example, a
plurality of components 3430 may include a direct current converter
converting AC power provided from an external power supply into DC
power, a driving chip controlling driving of the light source part
3200, and an electrostatic discharge (ESD) protective device.
[0241] The inner case 3500 receives the circuit part 3400 therein.
The inner case 3500 may include a receiving part 3510 to receive
the circuit part 3400. For example, the receiving part 3510 may
have a cylindrical shape. The shape of the receiving part 3510 may
be changed according to the shape of the radiator 3300. The inner
case 3500 may be received in the radiator 3300. The receiving part
3510 of the inner case 3500 may be received in a receiving part
which is formed at a bottom surface of the radiator 3300.
[0242] The inner case 3500 may be coupled with the socket 3600. The
inner case 3500 may include a connecting part 3530 coupled with the
socket 3600. The connecting part 3530 may have a thread structure
corresponding to a screw groove structure of the socket 3600. The
inner case 3500 is an insulator. Accordingly, the inner case 3500
prevents electric short between the circuit part 3400 and the
radiator 3300. For example, the inner case 3500 may include a
plastic or resin material.
[0243] The socket 3600 may be coupled with the inner case 3500. In
detail, the socket 3600 may be coupled with the connecting part
3530 of the inner case 3500. The socket 3600 may have the same
structure as that of a conventional incandescent light bulb. The
socket 3600 is electrically connected to the circuit part 3400. For
example, the circuit part 3400 and the socket 3600 may be connected
to each other by a wire. If external power is applied to the socket
3600, the external power may be transferred to the circuit part
3400. The socket 360 may have a screw groove structure
corresponding to a thread structure of the connecting part
3550.
[0244] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
* * * * *